Hmm. I'm sitting and typing this right now, and looking at my elbow and it appears to be a 90-degree angle. Also, there's different things you can do to your

Hmm. I'm sitting and typing this right now, and looking at my elbow and it appears to be a 90-degree angle. Also, there's different things you can do to your arm that require a sling. I didn't require a cast for my injury, but even if I did, the sling's purpose is mainly to keep your arm in a neutral position, keep you from bearing weight with it, and keep your upper arm from having to deal with the weight of the cast. It doesn't completely immobilize you; you can usually still rotate your arm enough to use a keyboard. Obviously, though, this depends on your exact injury and what's been done to your arm.